In data transmission networks, cross-connect connectors (such as BIX, 110, 210, etc.) are commonly used in telecommunication rooms to interconnect the ends of telecommunications cables, thereby facilitating network maintenance. For example, the prior art reveals cross connectors comprised of a series of isolated flat straight conductors each comprised of a pair of reversed Insulation Displacement Contact (IDC) connectors connected end to end for interconnecting a conductor of a first cable with the conductors of a second cable.
As known in the art, all conductors transmitting signals act as antennas and radiate the signal they are carrying into their general vicinity. Other receiving conductors will receive the radiated signals as crosstalk. Cross talk typically adversely affects signals being carried by the receiving conductor and must be dealt with if the strength of the received crosstalk exceeds certain predetermined minimum values. The strength of received cross talk is dependant on the capacitive coupling between the transmitting conductor and the receiving conductor which is influenced by a number of mechanical factors, such as conductor geometry and spacing between the conductors, as well the frequency of the signals being carried by the conductors, shielding of the conductors, etc. As signal frequency increases, the influence of even quite small values of capacitive coupling can give rise to significant cross talk having a deleterious effect on signal transmission.
Systems designed for the transmission of high frequency signals, such as the ubiquitous four twisted pair cables conforming to ANSI/EIA 568, take advantage of a variety of mechanisms to minimise the capacitive coupling between conductors both within and between cables. One problem with such systems is that, although coupling, and therefore crosstalk, is reduced within the cable runs, conductors within the cables must inevitably be terminated, for example at device or cross connector. These terminations introduce irregularities into the system where coupling, and therefore cross talk, is increased. With the introduction of Category 6 and Augmented Category 6 standards and the 10 GBase-T transmission protocol, the allowable levels for all kinds of internal and external crosstalk, including Near End Crosstalk (NEXT), Far End Crosstalk (FEXT) and Alien Crosstalk, have been lowered. As a result, the prior art connectors and interconnectors are generally no longer able to meet the allowable levels for cross talk.
Additionally, although long cable elements such as the twisted pairs of conductors achieve good crosstalk characteristics through appropriate twisting and spacing of the pairs of conductors, when viewed as a whole, the cable is subject to additional crosstalk at every irregularity. Such irregularities occur primarily at connectors or interconnectors and typically lead to an aggressive generation of crosstalk between neighbouring pairs of conductors which in turn degrades the high frequency bandwidth and limits data throughput over the conductors. As the transmission frequencies continue to increase, each additional irregularity at local level, although small, adds to a collective irregularity which may have a considerable impact on the transmission performance of the cable. In particular, unraveling the ends of the twisted pairs of conductors in order to introduce them into an IDC type connections introduces capacitive coupling between the twisted pairs.